Firefighters are among a group of patients treated at the scene of a chemical tanker fire that shut parts the M6 motorway.

West Midlands Ambulance Service said nine people received treatment for breathing difficulties at the scene of the accident, but it is not known exactly how many were fire service officers.

A spokesman said: "Nine patients are being treated for breathing difficulties as a result of fumes from the lorry fire. Several are firefighters, one is the lorry driver, and others are members of the public."

He said the patients were not reported to be seriously injured and all were "self-presenting" to medical staff on the scene. They would probably be taken to local hospitals as a precautionary measure.

The chemical tanker caught fire at around 9.30am on Wednesday after the vehicle suffered a tyre blow-out. Some motorists were forced to leave their cars after firefighters put in place a large exclusion zone around the scene of the accident.

The northbound carriageway was closed between J3 and J3A and southbound between J4 and J3, the Highways Agency said. Motorists were asked to avoid the area as long delays were expected.

Also closed was the M6 J2 and J3 northbound access as well as the slip road from Corley services between J3 and J4 on the M6 in both directions.

A spokeswoman for Warwickshire Police said: "Due to the motorway being closed, there is a massive tailback of traffic and we are currently advising people to stay away from the area. Fire service are in attendance at the moment at the vehicle and it looks like it could be quite a long job."

WMAS said three ambulances were at the scene, as well as a rapid response vehicle, two paramedic officers and some specialist hazardous area response teams.